There does not appear to be a function when I create a custom report to request a page break or sort break key. That's so common to general report writers, so am I not seeing how to do that in MLS? Or does that function not exist? For example, I wish to create a report by criteria that appears on every MLS record. I want that to appear only once at the top of the page, but not on each detail line. I also want to have a page break when that criteria changes value. Criteria could be something such as a zip code or a town name. Another use for me would be able to print all home teaching families by their assigned home teachers, with a page break occurring when the HT companionship changes.

You're correct that MLS does not have a general ability to break pages on a criterion. And given that MLS development is now a lower priority, I doubt that such a feature will ever be added to the desktop application. But that doesn't mean that you can't accomplish what you want.

Personally, I never use custom reports in MLS as my final step; instead, I use a custom report to generate the data I need, then I copy the data and paste it into a spreadsheet, where I can do formatting (conditional formatting, headers, footers, repeating rows, date formats, borders, etc.) to produce the final output I want.